There are waterproof know closures including a perforable membrane, generally made of synthetic elastic material, applied to the mouthpiece of a bottle by means of a capsule, generally made of aluminium, whose central portion is perforated or removable to allow an operator to connect an outflow for phleboclysis or hypodermoclysis to the bottle perforating it on the membrane by means of a perforator of said outflow.
A drawback of said closures consists in that, being constituted by several elements of different materials, they are difficult to be made and they are expensive.
Further drawback of said known closures consists in that they cannot hold the perforator provoking the risk of accidental detachment of the outflow or the risk of leakage due to excessive inclinations of the perforator.
Further drawback consists in that the interstices between the membrane and the capsule of said known closures can become dirty and/or contaminated and difficult to be cleaned and to be disinfected.